The hugely popular micro-blogging service Twitter has come from a standing start in 2006 to become as well known as Facebook in the US, with African Americans proving particularly keen on "tweeting".

Some 87% of Americans know what Twitter is, compared with just 5% two years ago, giving it almost the same visibility as Facebook, which wins 88% awareness. But according to a study by the polling firm Edison Research, actual usage still lags far behind. Just 7% of Americans are on Twitter, while 41% are on Facebook.

Twitter users tend to be disproportionately young, affluent and technology-savvy. And, in a curious finding, Twitter is particularly popular in the black community – 25% of US users are African American, roughly double their representation in the overall population.

Tom Webster, Edison vice-president, said: "African Americans are more likely to be status updaters in general, whether it's on Twitter, on Facebook or on other social networks. They're more prominent adapters of mobile technology in general. You have African Americans out in front a little bit in mobile technology, the mobile web and SMS's [text messages]."

A report last year by the Pew Internet & American Life Project found 26% of African American internet users tweeted, compared with 19% of white users. Commentators have remarked on the prevalence of "trending topics" reflective of African American culture. Edison suggested that black users tended to use Twitter in a more "conversational" way than a "broadcast" approach of posting observations.

In encouraging findings for advertisers, 44% of Americans on Twitter are aged 18 to 34, while 24% live in homes with annual income above $75,000 compared with a national average of 18%. Twitter, founded in Silicon Valley four years ago, dipped its toes into the commercial sphere last month by introducing "promoted tweets" that integrate ads.

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